#!/bin/sh

TMPDIR=${TMPDIR/%\/}

echo "$TMPDIR"

exit


abc=""
#判断变量是否存在或者是否为空值
if [ $abc ]
then
	echo "abc 存在"
else
	echo "abc 不存在"
fi


exit

a="GikkiAres"
a1="TinyWind"
echo "I am $a1 23"

readonly a2="sss"
# a2="222"
echo $a2

#删除变量
a="333"
echo ${a}
unset a
a="444"
echo ${a}

#查找子串
string="runoob is a great site"
echo `expr index "$string" io` 